1. Field of the Invention
The present invention relates to a transfer type working system of the type that a transfer line for intermittently conveying workpieces is provided thereon with plural stages of working stations disposed in front and rear relationship so that each workpiece may be worked upon by plural working processes by machine tools provided at the respective working stations.
2. Description of the Prior Art
It has been usual hitherto with this kind of system that the machine tool provided at each of the working stations is a machine tool of a single function providing only a single working process out of the plural working processes of the entire line. Consequently, replacement of the machine tool with a different one or the provision of an additional transfer line becomes necessary when any of the working processes is changed or the kind of workpiece is changed.
In addition, in usual systems, when the machine tool is to be replaced, the manufacturing operation is stopped. When an additional transfer line is to be provided, the floor space of a factory is largely occupied thereby. Thus both of the previous cases involve inconvenience or disadvantages that result in a lowering of production efficiency.
Especially recently, it has been desired that a working system not only have a lot production form in which workpieces of a single kind are processed, but also have various production forms of processing the workpieces such as a multi-kind random production form in which plural kinds of workpieces are conveyed at random on the same transfer line, a multi-process lot production form in which workpieces requiring plural working processes are processed for a short time by plural machine tools, each having multi-working processes and also a multi-kind multi-process random production form of the type that the foregoing two forms are combined together. However, it is hardly possible for the conventional system to meet such desires by the replacement of machine tools or the additional provision of another transfer line.